A simple high-resolution on-line x-ray imaging crystal spectrograph for laser-plasma interaction studies

A simple, high-resolution x-ray imaging crystal spectrograph is described f or on-line measurements and analysis of x-ray emission from laser-produced plasmas in the wavelength range of similar to 5-12 Angstrom. The spectrogra ph uses a planar TAP crystal for dispersion and a phosphor-coated optical f iber plate followed by an image intensifier and a charge-coupled device cam era for detection. The spectrograph covers a wavelength range of similar to 1.4 Angstrom in a single shot about a desired wavelength setting with a sp ectral resolution of similar to 0.012 Angstrom. It also has a design flexib ility to cover the full spectral range of 5-12 Angstrom in a single shot wi th a spectral resolution of similar to 0.040 Angstrom. The spectrograph is particularly suited for studies involving low vacuum environment, e.g., pla sma interaction with a background gas, laser interaction with a gas jet, et c., which preclude the use of other on-line detectors such as open-ended mi crochannel plates. An example of space resolved x-ray emission from laser-p roduced magnesium plasma expanding in a helium gas is also presented. (C) 2 000 American Institute of Physics. [S0034-6748(00)03207-X].